1. Quadrilaterals & Parallelograms
Analytic Geometry
Unit 1: Similarity, Congruence & Proofs

2. Parallelogram 2 pairs of opposite sides are parallel
2 pairs of opposite angles are ≅
Consecutive angles are supplementary
Diagonals bisect each other
∠A+∠B=180 ∠C+∠B=180
∠A+∠D=180 ∠C+∠D=180

3. Rectangle AC≅ DB All properties of a Parallelogram plus
Diagonals are ≅
4 ≅ right angles
AC≅ DB

4. Rhombus All properties of a Parallelogram plus
Diagonals are perpendicular (they make 90 degrees)
Diagonals bisect opposite angles
4 ≅ sides

5. Square
All properties of a Parallelogram plus All properties of a Rectangle plus All properties of a Rhombus
AC≅ DB

6. Trapezoid
Exactly 1 pair of parallel sides

7. Isosceles Trapezoid AC≅ BD Exactly 1 pair of parallel sides
Base angles are ≅
Opposite angles are supplementary
1 pair of ≅ legs
Diagonals are ≅
AC≅ BD
∠A+∠B=180 ∠C+∠B=180
∠A+∠D=180 ∠C+∠D=180

8. Kite 2 pairs of consecutive sides are ≅
1 pair of opposite angles are ≅
Diagonals are perpendicular

9. Helpful formulas
Slope Formula: Given the two points (x1, y1) and (x2, y2) Distance Formula: Given the two points (x1, y1) and (x2, y2), the distance between these points is given by the formula: